spatial-databases

## What I do - Query spatial data efficiently - Implement location-based queries and services - Design spatial indexes - Work with geographic coordinate systems - Process geospatial data ## When to use me When building location-based services, GIS applications, or any system requiring spatial queries. ## Key Concepts ### Spatial Data Types - Points, Lines, Polygons - MultiPoint, MultiLine, MultiPolygon - Geometry vs Geography - Z coordinates (3D) - M coordinates (measures) ### Coordinate Systems - WGS84 (EPSG:4326) - Web Mercator (EPSG:3857) - UTM zones - Coordinate transformations - Projected vs geographic CRS ### Spatial Indexing - R-trees - Quadtrees - Geohash - H3 (Uber's hexagonal hierarchy) - Index optimization ### Spatial Functions - Distance calculations - Area computations - Buffer operations - Union/Intersection - Point-in-polygon - Nearest neighbor ### Common Queries - Find points within radius - Find polygons containing point - K-nearest neighbors - Route between points - Spatial joins - Heatmap generation ### Database Support - PostGIS (PostgreSQL) - MySQL spatial extensions - SQL Server spatial - Oracle Spatial - MongoDB geospatial - Redis geospatial ### Use Cases - Ride-sharing/mapping - Store locators - Geofencing - Asset tracking - Weather analytics - Urban planning